In general, common keys of the same kinds are used in construction equipment such as an excavator so as to effectively manage the equipment. Consequently, in the case where a door of the construction equipment is not closed or the common key is applied even though the door is closed, others can approach the construction equipment and then open the door to drive the construction equipment, which may cause a theft case or a safety accident case.
In order to prevent such a problem, construction equipment with a special device, such as a password input unit, for driving the construction equipment have been developed and used recently.
In the case where the special device is used, if an ignition is turned on for the purpose of preheating a heater or an engine, it cannot effectively protect the construction equipment from theft or safety accident since the engine is driving.